This invention relates to rigid polyurethanes characterized by high flexural modulus, high Shore D hardness, and good abrasion resistance that are prepared from allophanate-modified aliphatic and/or cycloaliphatic polyisocyanurates.
The use of polyurethanes in the manufacture of bowling balls is known. One object of the present invention was to obtain polyurethanes having improved flexural modulus, hardness, and abrasion resistance for use in such applications. Another object was to prepare polyurethanes using lower volatility polyisocyanates than is typical for such applications and thereby to reduce the likelihood of releasing isocyanate-containing compounds into the atmosphere where they could pose environmental or health risks. It has now been found that the use of allophanate-modified aliphatic and/or cycloaliphatic polyisocyanurates in combination with high functionality polyols can provide such advantages.